Striker Kyogo Furuhashi has left Celtic for French club Stade Rennes in a £10m move.
The 30-year-old departs the Scottish Premiership champions three and a half years after former manager Ange Postecoglou brought him to the club from J League side Vissel Kobe.
He scored 85 goals in 165 appearances for the Hoops, winning three Premiership titles, three League Cups and the Scottish Cup twice.
Celtic boss Brendan Rodgers revealed Kyogo told him a “number of months” ago that he wanted to move to one of Europe’s top five leagues following a conversation with Japan boss Hajime Moriyasu, who has previously publicly criticised the quality of the Scottish Premiership.
He has signed a two-and-a-half-year deal with the side sitting 17th in Ligue 1.
Celtic added a forward replacement for Kyogo in this transfer window, earlier announcing a deal to bring Jota back to the club.
Rodgers said: “Kyogo had expressed an interest to leave a number of months back and then that expression becomes stronger and then it gets to the stage where he clearly very wants to leave.
“Then, sadly, we have to do a deal and look to finalise that for him. He’s been an incredible player for the club for the three and a half years he’s been here and he’s not someone that we wanted to lose, but we have to accept where he’s at.
“You can achieve many things here at Celtic. The league might not be one of the top five leagues in the world, but this is a league where you can really develop and show your talent at the very highest level.
“When I arrived here, Kyogo hadn’t scored a goal in the Champions League. If he leaves, he’s then shown that he can play at that level.
“Within the Japanese squad, there are obviously many really good players in there, but I think that you can show that by being here and winning and playing the type of football that we play and playing at the highest level, that you can still achieve everything that you would like to.
“There can be issues around the timing, but it’s not something that’s just been sprung on us. We understand that we were going to lose him and we understand that we have to replace that quality to keep the team moving forward.
“That’s something that has been ongoing for a little while and hopefully we can come out of the window with a stronger squad.”
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